1. Field of the Invention
This invention relates to the configuration and operation of logically partitioned computational machines. More particularly, the invention is directed to dynamic logical partitioning for NUMA machines and clusters.
2. Description of the Prior Art
By way of background, a logically partitioned computational machine allows system resources such as CPUs, memory and input/output (I/O) hardware to be assigned to one or more logical partitions or containers. In modern dynamically partitioned machine environments, partitions can be reconfigured without having to reboot, allowing CPU, memory and I/O resources to be added to, deleted from, or moved between running partitions. Dynamic logical partitioning has been implemented in NUMA (NonUniform Memory Access) machines wherein interconnected NUMA hardware nodes share memory and I/O resources. Partitions may be contained within single nodes or may span across several nodes, depending on configuration requirements. However, there can be performance differences depending on whether a partition crosses NUMA node boundaries. Multi-node partitions may experience increased latency for remote memory and I/O accesses that require internodal communication, whereas single-node partitions may suffer from local bandwidth congestion on local memory and I/O busses.